There are many manufacturing circumstances where predetermined quantities of granular materials must be provided to different locations where the materials are to be put to specific use. Examples of manufacturing methods requiring the blending of one or more granular or powdered materials with a carrier material include blending a paint by mixing assorted particulate fillers or dyes with a carrier fluid, mixing different powdered ingredients to form a blended fertilizer, forming explosive materials, blending quantities of coffees and/or additives, or providing controlled flows of powdered materials to form drilling mud.
A common factor in all such applications is that one or more granular materials has to be contained and controlled quantities thereof extracted and delivered at a distance. The supply is periodically replenished as needed. Precise control must be exercised over the timing and flow rates of individual material deliveries, and also over the sequence of the controlled deliveries.
Many granular or powdered materials in dry form are typically contained and transported in sacks of varying standardized sizes. The simplest technique for using such materials is for individual workers to lift and manipulate individual sacks over a funnel or other inlet, cut the sack and pour out a quantity of the contents to weigh the same. The weighed particulate material is then moved by conventional moving means, e.g., a conveyer belt, an auger, or the like, to a point where it combines with one or more other granular or liquid carrier materials. The problem with this long-used technique is that there is often spillage and consequential waste in handling the materials. This adds to the overall costs, not just because of the value of the wasted material, but also because it takes manpower to clean up spills. Spillage of certain materials can also pose health and/or fire hazards. Even further, where relatively large quantities of one or more granular materials must be handled with significantly different quantities of other granular materials, the necessary synchronization of deliveries can be difficult, time-consuming, and expensive.
For certain simple applications, e.g., repeatedly delivering set quantities of a single granular material to a single reception point, there are a number of well-known handling systems and methods. Many applications are more complex and may involve varying flow rates, materials of different average particle size, and multiple or movable delivery locations in use. There is, therefore, a real need for a programmable, modular system which selectively operates one or more modular units in cooperation to enable a single human controller to deliver different particulate, powdered or granular materials at selected respective rates to a number of delivery points while avoiding the inconvenience, cost and difficulties of spillage and waste.
The apparatus and method according to the present invention are intended to address this need.